Various plastic lenses such as prism lenses are produced by, for example, a method in which a resin material is poured into a die, a transparent plastic substrate is placed on the resin material, and the resin material is cured by being heated or by being irradiated with an active energy ray. Therefore, the resin material used to produce plastic lenses needs to have, for example, optical properties such as a high refractive index and high transparency of a cured product, a low viscosity without using a solvent so that the resin material completely fills every cavity of a die and thus has the same shape as that of the die, and good adhesiveness to a transparent plastic substrate.
Among resin materials used for plastic lenses, a compound having a fluorene skeleton has received attention because such a compound forms into a cured product having a high refractive index. However, such a compound has poor adhesiveness to a plastic film substrate such as a polyethylene terephthalate film and thus needs to be used in the form of a mixture with other compounds.
An example of a technique of improving the adhesiveness to a polyethylene terephthalate film using a compound having a fluorene skeleton is a plastic lens resin composition including a diacrylate compound having a fluorene skeleton and ortho-phenylphenoxyethyl acrylate (refer to PTL 1). Such a plastic lens produced from the resin composition has good adhesiveness to a substrate just after the production, but the adhesiveness to a substrate degrades over time and the storage stability is low. In particular, when the plastic lens is stored in a high-temperature and high-humidity environment, for example, transported by ship, the adhesiveness considerably degrades and the plastic lens is raised or detached from the substrate.